In sub-Saharan Africa (sSA), the vast majority of the millions of pregnant women who are tested and counseled for HIV every year test negative for HIV antibodies. Keeping these women uninfected is a critical component of the World Health Organization (WHO) global strategy fror prevention of mother-to-child HIV transmission (PMTCT). Evidence shows that these women are at continuous risk of HIV acquisition during pregnancy and breastfeeding with HIV incidence rates ranging between 2 and 17 infections per 100 person years. HIV acquisition during pregnancy or breastfeeding puts mothers and babies at high risk for vertical HIV transmission because of the peak viremia that follows incident HIV infection in the mother. WHO thus recommends that in generalized epidemic settings, pregnant women who test HIV negative on their first antenatal visit retest in late pregnancy in order to detect incident infections and take appropriate PMTCT measures. However, this recommendation falls short of addressing the risks of incident HIV infection during breastfeeding and the need for primary HIV prevention. This study will test the hypothesis that extended repeat HIV testing and enhanced counseling (HTEC) during late pregnancy and breastfeeding can increase and/or sustain risk reduction behaviors and prevent incident STI and HIV infections among HIV-uninfected pregnant women and that couple HTEC can further enhance this effect. We will conduct a stratified randomized trial involving 1,230 HIV-uninfected pregnant women presenting individually (n=410) or in couples (n=410 women and 410 partners) in an urban and a rural public hospital in Uganda. Individual women and couples will be randomized to receive either repeat HIV testing and standard counseling (HTSC) in late pregnancy as per the WHO recommendation or repeat HIV testing and enhanced counseling (HTEC) during late pregnancy and breastfeeding (at 3, 6 12, 18 and 24 months or 6 weeks after the end of breastfeeding). Enhanced counseling will emphasize the concept of an HIV-free and healthy baby and family based on primary prevention, adequate infant feeding and family planning. Our specific aims will be: 1) to assess the effect of extended repeat HTEC on sexual risk behavior and the incidence of sexually transmitted infections (STIs) and HIV in uninfected pregnant and lactating women presenting individually; 2) to assess the effect of extended repeat couple HTEC on sexual risk behavior and the incidence of STIs and HIV in uninfected pregnant and lactating women presenting with their partner, and 3) to assess the costs and estimate the cost-effectiveness of the intervention. We will compare the frequency of unprotected sex, and incidences of STI, HIV and recurrent pregnancies in intervention and comparison arms. Analyses will focus on the effect of individual and dyadic factors (couple communication and support) on risk behaviors and STI/HIV incidence. The findings of this study will inform policy about the effectiveness of retesting and counseling HIV-negative pregnant and lactating women in sSA.